Electric discharge tube



July 13,1926. 1,592,387' I G. SEjBT ELECTRIC DISCHARGE TUBE 7 Filed August 26. 1921 "Patented July 13, 1926.

UNITED STATES PATENT OFFICE.

GEORG SEIB'I, F BERLIN-SOHONEBERG, GERMANY.

nnsc'rmc. mscnaner. runs.

Application fled August-26, 1821, Serial No. 495,504, and in Germany October 24, 1913.

(cmursnumsa rm: raovrsrons or "rim ACT or mmcn a, 1921,41 era-r. 1.., 1313.

It is known that an ionized gas may under suitable conditions serve for detect g plifying orgenerating alternatingcurrents: known examples are the Fleming valve, the DeForest audion, the Poulsen arc and the Lieb'en tube.

According to this invention the freed The invention is illustrated b the accompanyingdrawings, in which 1i e parts are similarly designated, and in which- Figure 1 illustrates diagrammatically a vacuum tube constructed in accordance with my I invention.

Fig. 2 shows a modification.

Fig. 3 illustrates the application of an auxdiliary potential connected-to one of the gri s. v

, In a vacuous glass vessel is arranged-a filament F heated by a small battery A. From the filament pass negative ions which traverse the grid or screen G, G before reaching the metal'plate. M. T is a telephone, J a galvanometer and Han auxiliary atteg. The wires (1, b, connected to the grid G: lead to the circuit whose oscillation is to be detected or amplified. The metal "plate M has in it slots which correspond to the spaces between the two combs G, G of the grid and inthis instance the grid M- forms part of or also'acts as anode.

If the spaces between the combs are exactly opposite the slots in grid M, the

greater portion of'the stream of ions ceedmg rom'F will pass through the p ate M and only a few wil impinge on the metal of M. If, however, a diflerence of potential G will deflect the stream of ions at ri ht angles to its previousdirection.

he consequence is that a greater portion of the stream of ions falls upon the late M and a smaller portion passes throug the s o If on the other hand the slots in M are exactly opposite the teeth of the grid G, G, nearly the whole stream of ions which pass the grid will, fall upon the plate-M and only when the grid is. electrically excited will the greater 1portion pass through the slots.

It wi be seen from the foregoing that a is known ma be applied at a, b, the electric field between the grid G G possesses the properties of a valve by which the stream of ions between F and M is controlled.

, Figure 2' shows another modification.

In this in rear of the grid M a solid metal plate V is provided. a I

In considering the action of this arrangement we-must distin uish between the case which they are opposite the strips of the grid M. In the first case, on the excitation under some circumstances be considerably increased if at the combs G G asfshown in Figure 3, an auxiliary potential is applied which is preferably variable, Obviously the stream of ions can by this means be so deflected that it passes through the grid M in the most favourable form. In ractice such favourable conditions cannot e exactly suited by the manufacture of the arrangement. The said auxiliary potential is preferably employed for regulatlng the formation of the stream.

In the foregoing arrangements it has been assumed that the deviation of the stream of ions resulted from an electrical field. As etic forces act inthe same manner and t e alteration of movement is at right angles to the magnetic field and the original direction ofthe stream of-ions.

If, for example, a coil through which a current is passing be moved over the tube the ions emitted fromthe heated wire are deflected in a peripheral direction.

1. In a discharge tube in which an 101110 stream passes from one point to another, a bi-part, ion-deflecting screen a 11d a slotted plate, both in the path of the ionic stream.

2. In a discharge tube in which an iomc in which the spaces etween the combs G, G are opposite to the slots and the case in of the combs G G 'the stream of ions which reaches V decreases; in the second case it stream passes from one point to another, a

bi-part, ion-deflecting screen and a slotted plate in the path of the ionic stream, and another plate beyond the slotted plate.

3. In a vacuum tube, a filament sending out an ionic stream, means for conductin oif the said ionic stream, a 'd traverse 'by saidstream, a-second gri impinged by the said s neam after having passed said first grid, means for controlling the passage of the ions through the said two grids, and means for applying an auxiliary potential to the parts of the said ion-deflecting grids tor regulating the formation of the ionic stream, said grids lying in difierent planes. In a discharge tube, a heated element, a Eli-part and successively arran ed.

5. In a discharge tu e, a heated element,

a lei-part grid, a second grid and a plate arranged successively and spaced from one another, the electrons passing from said elemerit successively to the two gridsand then to the plate; I

6. In a discharge tube, a heated element, a plurality of grids arranged in spaced succession, one 0 said grids being a bi-part grid, and means to deflect the ion-stream leaving the latter grid.

'd and a second grid, spaced unease? 7. In a discharge tube, a heated element, a bi-part grid, a second grid and a plate, and means to deflect the ion-stream leaving' the bi-part rid.

8. In a t ermionic vacuum tube, a cathode arranged to be heated, a plurality of grid-like electrodes arranged in spaced and substantially parallel planes.

9 In a t ermionio vacuum tube, a cathode and a plurality of grid-like electrodes the spaces in one grid corresponding sub 'stantially to the spaces in the other grid.

10. In a thermionic acuum tube, a cathode, a two-part grid, and a second grid, arranged in succession, and means to maintain a potential difference between the parts of the two-part grid.

In testimony whereof I have signed this specification.

DR. GEORG SEIBT. 

